Abstract: A master/slave discharge valve assembly for pressurized fluid containment systems includes a primary valve chamber, for connection to a fluid pressure source, formed by an eccentrically disposed first longitudinal bore and a secondary valve chamber defined by a second bore generally parallel to that of the primary chamber, communicating at one end with the primary valve chamber and a the other end with a discharge port. A displaceable primary valve member is positioned within the primary valve chamber. A slave valve member and an actuating piston are to open the slave valve member and permit a holding portion of pressurized fluid to vent to the atmosphere, thereby permitting the pressurized fluid to open the first valve member and allow pressurized fluid out the discharge port. A master/slave valve assembly according to the invention is of lower cost to manufacture as well as simpler and sturdier in construction than known valves for carbon dioxide fire suppression systems.

Abstract: A portable disposable fire extinguisher comprises a container for fire extinguishing medium, a discharge head, and a valve device within the discharge head for controlling a discharge passage. The valve is normally biased to a closed position by a return spring and by pressure in the container. The discharge head is constituted by a one-piece moulding providing a valve body, a carrying handle, a discharge nozzle and an operating lever which is connected to the valve body by a plastic hinge. Accidental operation of the lever is prevented by a discardable stop plate forming part of the moulding and connected thereto by frangible connections.

Abstract: Containers such as liquefied gas cylinders are weighed in situ using a balance comprising a pneumatic actuator connected between a support temporarily installed above a container to be weighed and the container itself. Gas pressure is applied to the actuator to lift the container off the surface on which it is standing, and the pressure required to hold it off that surface is measured to indicate the weight of the container. A limiting valve is associated with the actuator so as to limit pressure therein to that required to lift the container.